Mobile communication method and mobile station

ABSTRACT

A mobile communication method according to the present invention includes the steps of: (A) transmitting, from a mobile station (UE) to a radio base station (eNB), a “Measurement Report” including a measurement result of a “MeasObject”, when the mobile station (UE) links and manages a “MeasID”, the “MeasObject”, and a “ReportConfig”, and when the mobile station (UE) determines that the “ReportConfig” is satisfied; and (B) determining, at the mobile station (UE), whether or not to release the “MeasID” according to a type of a carrier designated by the “MeasObject”, when a change has occurred in a combination of the primary carrier and the secondary carriers.

TECHNICAL FIELD

The present invention relates to a mobile communication method and amobile station.

BACKGROUND ART

In an LTE (Long Term Evolution) Release-8/9 mobile communication system,a radio base station eNB is configured to transmit “MeasConfig”including “MeasObject”, “ReportConfig”, and “MeasID” to a mobile stationUE.

Here, the “MeasObject” is information for designating a measurementobject carrier based on RAT and a frequency, the “ReportConfig” isinformation for designating an event such as A1 to A5 or B1 and B2, or atransmission trigger of “Measurement Report” such as “Periodical”.

Furthermore, the “MeasId” is information for linking the “MeasObject” tothe “ReportConfig” as shown in FIG. 7.

The mobile station UE is configured to perform only measurement of the“MeasObject” associated with the “ReportConfig” based on the “MeasId”.

Here, in the LTE Release-8/9 mobile communication system, when“Inter-frequency Handover (different frequency handover)” or“Inter-frequency Re-establishment (different frequencyre-establishment)” has been generated, the mobile station UE isconfigured to autonomously switch a “MeasId” link destination.

For example, as shown in FIG. 7 and FIG. 8, when a serving cell(Serving) is changed from a cell in “F1” designated by “MeasObject#1” toa cell in “F2” designated by “MeasObject#2” by the “Inter-frequencyHandover” or the “Inter-frequency Re-establishment”, the mobile stationUE is configured to change a link destination of “MeasId#1” and“MeasId#2” from the “MeasObject#1” to the “MeasObject#2”, and change alink destination of “MeasId#3” and “MeasId#4” from the “MeasObject#2” tothe “MeasObject#1”.

Furthermore, as shown in FIG. 7 and FIG. 9, when the serving cell(Serving) is changed from the cell in the “F1” designated by the“MeasObject#1” to a cell in “F4”, in which the “MeasObject” has not beenset, by the “Inter-frequency Handover” or the “Inter-frequencyRe-establishment”, the mobile station UE is configured to release the“MeasId#1” and the “MeasId#2” linked to the “MeasObject#1”.

Then, a radio base station eNB is configured to add “MeasObject#4” fordesignating the “F4” and link the “MeasId” to the “MeasObject#4” by “RRCConnection Reconfiguration” immediately after “Handover Command” or“Re-establishment”.

In an LTE-Advanced scheme (LTE Release-10 scheme) which is a nextgeneration of the LTE Release-8/9 scheme, the mobile station UE isconfigured to be able to perform CA (Carrier Aggregation) communicationwith the radio base station eNB by using PCC (a Primary ComponentCarrier) and one or a plurality of SCCs (Secondary Component Carriers)having different carrier frequencies (EARFCN: E-UTRA Absolute RadioFrequency Channel Number).

Such a CA communication has a problem that since a serving cell existsin each PCC and each SCC, it is not possible to apply a method ofswitching and a method of releasing the aforementioned “MeasId”.

Therefore, the present invention has been achieved in view of theabove-described problems, and an object thereof is to provide a mobilecommunication method and a mobile station, by which it is possible toappropriately switch and release “MeasId” in CA communication.

SUMMARY OF INVENTION

A first aspect of the present invention is summarized as a mobilecommunication method in which a mobile station communicates with a radiobase station by using a primary carrier and one or a plurality ofsecondary carriers having different carrier frequencies, the methodincluding the steps of: (A) transmitting, from the mobile station to theradio base station, a measurement report including a measurement resultof a measurement object carrier, when the mobile station links andmanages a measurement ID, the measurement object carrier, and a reportcondition, and when the mobile station determines that the reportcondition is satisfied; and (B) determining, at the mobile station,whether or not to release the measurement ID according to a type of acarrier designated by the measurement object carrier, when a change hasoccurred in a combination of the primary carrier and the secondarycarriers.

A second aspect of the present invention is summarized as a mobilestation, which is configured to communicate with a radio base station byusing a primary carrier and one or a plurality of secondary carriershaving different carrier frequencies, including: a transmission unitconfigured to transmit a measurement report including a measurementresult of a measurement object carrier to the radio base station, when ameasurement ID, the measurement object carrier, and a report conditionare linked and managed, and when it is determined that the reportcondition is satisfied; and a measurement processing unit configured todetermine whether or not to release the measurement ID according to atype of a carrier designated by the measurement object carrier, when achange has occurred in a combination of the primary carrier and thesecondary carriers.

A third aspect of the present invention is summarized as a mobilecommunication method, in which a mobile station communicates with aradio base station by using a primary carrier and one or a plurality ofsecondary carriers having different carrier frequencies, including: astep of releasing, at the mobile station, configuration informationrelated to the secondary carriers when a change has occurred in thecombinations of the primary carrier and the secondary carriers.

A fourth aspect of the present invention is summarized as a mobilestation, which is configured to be able to communicate with a radio basestation by using a primary carrier and one or a plurality of secondarycarriers having different carrier frequencies, is configured to releaseconfiguration information related to the secondary carriers when achange has occurred in the combinations of the primary carrier and thesecondary carriers.

As described above, according to the present invention, it is possibleto provide a mobile communication method and a mobile station, withwhich it is possible to appropriately switch and release “MeasId” in CAcommunication.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram showing the entire configuration of a mobilecommunication system according to a first embodiment of the presentinvention.

FIG. 2 is a functional block diagram of a mobile station according tothe first embodiment of the present invention.

FIG. 3 is a flowchart illustrating an operation of the mobile stationaccording to the first embodiment of the present invention.

FIG. 4 is a diagram for explaining a state in which measurementconfiguration is changed in the mobile station according to the firstembodiment of the present invention.

FIG. 5 is a diagram for explaining a state in which measurementconfiguration is changed in the mobile station according to the firstembodiment of the present invention.

FIG. 6 is a flowchart illustrating an operation of a mobile stationaccording to a second embodiment of the present invention.

FIG. 7 is a diagram for explaining a state in which measurementconfiguration is changed in a mobile station in the conventional art.

FIG. 8 is a diagram for explaining a state in which measurementconfiguration is changed in a mobile station in the conventional art.

FIG. 9 is a diagram for explaining a state in which measurementconfiguration is changed in a mobile station in the conventional art.

DESCRIPTION OF EMBODIMENTS Mobile Communication System According toFirst Embodiment of the Present Invention

With reference to FIG. 1 to FIG. 5, the configuration of a mobilecommunication system according to a first embodiment of the presentinvention will be described. The mobile communication system accordingto the present embodiment is an LTE-Advanced (LTE Release-10) mobilecommunication system.

In the mobile communication system according to the present embodiment,a mobile station UE is configured to be able to perform CA communicationby using PCC and one or a plurality of SCCs having different carrierfrequencies (EARFCN).

As shown in FIG. 1, the mobile communication system according to thepresent embodiment is configured to be able to use CCs of EARFCN #1through EARFCN #5 during the CA communication.

In the mobile communication system according to the present embodiment,as shown in FIG. 1, the mobile station UE performs CA communication bysetting the CC of EARFCN #1 as “PCC”, the CC of EARFCN #2 as “SCC #1”,and the CC of EARFCN #3 as “SCC #2”.

Furthermore, the serving cell in the PCC of the mobile station UE is“Pcell”, the serving cell in the SCC #1 of the mobile station UE is“Scell #1”, and the serving cell in the SCC #2 of the mobile station UEis “Scell #2”.

As shown in FIG. 2, the mobile station UE includes a re-establishmentprocessing unit 11, a handover processing unit 12, a measurementprocessing unit 13, and a transmission unit 14.

The re-establishment processing unit 11 is configured to perform aprocess related to reconnection (for example, Inter-frequencyRe-establishment) of the mobile station UE.

The handover processing unit 12 is configured to perform a processrelated to handover (for example, Inter-frequency Handover) of themobile station UE.

The measurement processing unit 13 is configured to perform ameasurement process of a measurement object carrier, which has beendesignated by a “MeasObject”, when a “MeasId”, the “MeasObject”, and a“ReportConfig” are linked and managed.

Furthermore, the measurement processing unit 13 is configured todetermine whether or not to release the “MeasId” according to the typeof CC designated by the “MeasObject”, when a change has occurred in thecombinations of the PCC and the SCCs. A detailed determination methodwill be described later.

The transmission unit 14 is configured to transmit a “MeasurementReport” including a measurement result of the “MeasObject” to a radiobase station eNB, when the “MeasId”, the “MeasObject”, and the“ReportConfig” are linked and managed and it is determined that the“ReportConfig” is satisfied.

Hereinafter, with reference to FIG. 3 to FIG. 5, a description will beprovided for an operation of the mobile station UE, when a change hasoccurred in the combinations of the PCC and the SCCs by “Inter-frequencyHandover”, “Inter-frequency Re-establishment” and the like in the mobilecommunication system according to the present embodiment.

As shown in FIG. 3, in step S101, the mobile station UE releases all“MeasIds” linked to the “ReportConfig” with a “trigger type” of“Periodical”.

In step S102, the mobile station UE determines whether or not the“MeasObject” for designating PCC (T-PCC) after change is managed.

When it is determined that the “MeasObject” is managed, the presentoperation proceeds to step S103A. When it is determined that the“MeasObject” is not managed, the present operation proceeds to stepS103B.

Then, for each “MeasId” managed by the mobile station UE, operations ofsteps S103A to S107A or operations of steps S103B to S107B areperformed.

In step S103A, the mobile station UE determines whether or not the“MeasObject”, to which a corresponding “MeasId” has been linked,designates PCC (S-PCC) before the change.

When it is determined that the “MeasObject” designates the PCC (S-PCC)before the change, the present operation proceeds to step S104A. When itis determined that the “MeasObject” does not designate the PCC (S-PCC)before the change, the present operation proceeds to step S105A.

In step S104A, the mobile station UE changes a link destination of the“MeasId” from the “MeasObject” having designated the S-PCC to the“MeasObject” having designated the T-PCC.

In step S105A, the mobile station UE determines whether or not the“MeasObject”, to which the corresponding “MeasId” has been linked,designates the SCC before the change.

When it is determined that the “MeasObject” designates the SCC, thepresent operation proceeds to step S106A. When it is determined that the“MeasObject” does not designate the SCC, the present operation proceedsto step S107A.

In step S106A, the mobile station UE releases the “MeasId”.

In step S107A, the mobile station UE maintains the link destination ofthe “MeasId” without a change. In addition, instep S107A, the mobilestation UE may release the “MeasId”.

In step S108A, the mobile station UE determines whether or not theprocesses of steps S103A to S107A have been performed for all “MeasIds”.

When it is determined that the processes of steps S103A to S107A havebeen performed, the present operation is completed. When it isdetermined that the processes of steps S103A to S107A have not beenperformed, the mobile station UE returns to step S103A and performs theprocesses of steps S103A to S107A for a subsequent “MeasId”.

Meanwhile, in step S103B, the mobile station UE determines whether ornot the “MeasObject”, to which the corresponding “MeasId” has beenlinked, designates the PCC (S-PCC) before the change.

When it is determined that the “MeasObject” designates the PCC (S-PCC)before the change, the present operation proceeds to step S104B. When itis determined that the “MeasObject” does not designate the PCC (S-PCC)before the change, the present operation proceeds to step S105B.

In step S104B, the mobile station UE releases the “MeasId”.

In step S105B, the mobile station UE determines whether or not the“MeasObject”, to which the corresponding “MeasId” has been linked,designates the SCC before the change.

When it is determined that the “MeasObject” designates the SCC, thepresent operation proceeds to step S106B. When it is determined that the“MeasObject” does not designate the SCC, the present operation proceedsto step S107B.

In step S106B, the mobile station UE releases the “MeasId”.

In step S107B, the mobile station UE maintains the link destination ofthe “MeasId” without a change. In addition, in step S107B, the mobilestation UE may release the “MeasId”.

In step S108B, the mobile station UE determines whether or not theprocesses of steps S103B to S107B have been performed for all “MeasIds”.

When it is determined that the processes of steps S103B to S107B havebeen performed, the present operation is completed. When it isdetermined that the processes of steps S103B to S107B have not beenperformed, the mobile station UE returns to step S103B and performs theprocesses of steps S103B to S107B for a subsequent “MeasId”.

Hereafter, with reference to FIG. 4 and FIG. 5, a description will beprovided for an example of a method of switching and a method ofreleasing the “MeasId” by the mobile station UE, when a change hasoccurred in the combinations of the PCC and the SCCs by the“Inter-frequency Handover”, the “Inter-frequency Re-establishment” andthe like in the mobile communication system according to the presentembodiment.

For example, a description will be provided for a case in which thecombinations of the PCC and the SCCs illustrated in FIG. 4 are changedto combinations of the PCC and the SCCs illustrated in FIG. 5. In such acase, “MeasObject#3” for designating the PCC (T-PCC) after the change ismanaged by the mobile station UE.

In such a case, since “MeasObject#1”, to which the “MeasId#1” has beenlinked, designates the PCC (S-PCC) before the change, the mobile stationUE changes the link destination of the “MeasId#1” from the“MeasObject#1” having designated the S-PCC to the “MeasObject#3” havingdesignated the T-PCC.

Similarly, since the “MeasObject#1”, to which the “MeasId#2” has beenlinked, designates the PCC (S-PCC) before the change, the mobile stationUE changes the link destination of the “MeasId#2” from the“MeasObject#1” having designated the S-PCC to the “MeasObject#3” havingdesignated the T-PCC.

Furthermore, since “MeasObject#2”, to which “MeasId#3” and “MeasId#4”have been linked, designates the SCC before the change, the mobilestation UE releases the “MeasId#3” and the “MeasId#4”.

Similarly, since “MeasObject#3”, to which “MeasId#5” and “MeasId#6” havebeen linked, designates the SCC before the change, the mobile station UEreleases the “MeasId#5” and the “MeasId#6”.

Furthermore, since “MeasObject#4”, to which “MeasId#7” has been linked,designates Non-configured CC, the mobile station UE maintains the linkdestination of the “MeasId#7” without a change.

Even in such a case, the mobile station UE may release the “MeasId#7”.

In addition, when “MeasConfig” has been newly notified at the time ofthe “Inter-frequency Handover”, the “Inter-frequency Re-establishment”and the like, the mobile station UE applies the “MeasConfig” afterperforming the procedure described above in detail.

In accordance with the mobile communication system according to thepresent embodiment, when a change has occurred in the combinations ofthe PCC and the SCCs by the “Inter-frequency Handover”, the“Inter-frequency Re-establishment” and the like, it is possible for themobile station UE to appropriately switch and release the “MeasId” basedon the type of CC of the link destination of the “MeasId”.

Mobile Communication System According to Second Embodiment of thePresent Invention

Hereinafter, with reference to FIG. 6, the mobile communication systemaccording to a second embodiment of the present invention will bedescribed while focusing on the difference from the mobile communicationsystem according to the above-mentioned first embodiment.

Hereinafter, with reference to FIG. 6, a description will be providedfor an operation of the mobile station UE when a change has occurred inthe combinations of the PCC and the SCCs by “Inter-frequency Handover”,“Inter-frequency Re-establishment” and the like in the mobilecommunication system according to the present embodiment.

As shown in FIG. 6, in step S201, the mobile station UE releases all“MeasIds” linked to the “ReportConfig” with a “trigger type” of“Periodical”.

In step S202, the mobile station UE determines whether or not the“MeasObject” for designating PCC (T-PCC) after change is managed.

When it is determined that the “MeasObject” is managed, the presentoperation proceeds to step S203A. When it is determined that the“MeasObject” is not managed, the present operation proceeds to stepS203B.

Hereinafter, for each “MeasId” managed by the mobile station UE,operations of steps S203A to S210A or operations of steps S203B to S210Bare performed.

In step S203A, the mobile station UE determines whether or not the“MeasObject”, to which a corresponding “MeasId” has been linked,designates PCC (S-PCC) before the change.

When it is determined that the “MeasObject” designates the PCC (S-PCC)before the change, the present operation proceeds to step S204A. When itis determined that the “MeasObject” does not designate the PCC (S-PCC)before the change, the present operation proceeds to step S205A.

In step S204A, the mobile station UE changes a link destination of the“MeasId” from the “MeasObject” having designated the S-PCC to the“MeasObject” having designated the T-PCC.

In step S205A, the mobile station UE determines whether or not CCdesignated by the “MeasObject”, to which the corresponding “MeasId” hasbeen linked, has been changed from SCC to Non-configured CC.

When it is determined that the CC has been changed from the SCC to theNon-configured CC, the present operation proceeds to step S206A. When itis determined that the CC has not been changed from the SCC to theNon-configured CC, the present operation proceeds to step S207A.

In step S206A, the mobile station UE releases the “MeasId”.

In step S207A, the mobile station UE determines whether or not the CCdesignated by the “MeasObject”, to which the corresponding “MeasId” hasbeen linked, has been changed from the Non-configured CC to the SCC.

When it is determined that the CC has been changed from theNon-configured CC to the SCC, the present operation proceeds to stepS208A. When it is determined that the CC has not been changed fromNon-configured CC to the SCC, the present operation proceeds to stepS209A.

In step S208A, the mobile station UE releases the “MeasId”.

In step S209A, the mobile station UE maintains the link destination ofthe “MeasId” without a change. In addition, in step S209A, the mobilestation UE may release the “MeasId”.

In step S210A, the mobile station UE determines whether or not theprocesses of steps S203A to S210A have been performed for all “MeasIds”.

When it is determined that the processes of steps S203A to S210A havebeen performed, the present operation is completed. When it isdetermined that the processes of steps S203A to S210A have not beenperformed, the mobile station UE returns to step S203A and performs theprocesses of steps S203A to S210A for a subsequent “MeasId”.

Meanwhile, in step S203B, the mobile station UE determines whether ornot the “MeasObject”, to which the corresponding “MeasId” has beenlinked, designates the PCC (S-PCC) before the change.

When it is determined that the “MeasObject” designates the PCC (S-PCC)before the change, the present operation proceeds to step S204B. When itis determined that the “MeasObject” does not designate the PCC (S-PCC)before the change, the present operation proceeds to step S205B.

In step S204B, the mobile station UE releases the “MeasId”.

In step S205B, the mobile station UE determines whether or not the CCdesignated by the “MeasObject”, to which the corresponding “MeasId” hasbeen linked, has been changed from the SCC to the Non-configured CC.

When it is determined that the CC has been changed from the SCC to theNon-configured CC, the present operation proceeds to step S206B. When itis determined that the CC has not been changed from the SCC to theNon-configured CC, the present operation proceeds to step S207B.

step S206B, the mobile station UE releases the “MeasId”.

In step S207B, the mobile station UE determines whether or not the CCdesignated by the “MeasObject”, to which the corresponding “MeasId” hasbeen linked, has been changed from the Non-configured CC to the SCC.

When it is determined that the CC has been changed from theNon-configured CC to the SCC, the present operation proceeds to stepS208B. When it is determined that the CC has not been changed fromNon-configured CC to the SCC, the present operation proceeds to stepS209B.

In step S208B, the mobile station UE releases the “MeasId”.

In step S209B, the mobile station UE maintains the link destination ofthe “MeasId” without a change. In addition, in step S209B, the mobilestation UE may release the “MeasId”.

In step S210B, the mobile station UE determines whether the processes ofsteps S203B to S210B have been performed for all “MeasIds”.

When it is determined that the processes of steps S203B to S210B havebeen performed, the present operation is completed. When it isdetermined that the processes of steps S203B to S210B have not beenperformed, the mobile station UE returns to step S203B and performs theprocesses of steps S203B to S210B for a subsequent “MeasId”.

In addition, when “MeasConfig” has been newly notified at the time ofthe “Inter-frequency Handover”, the “Inter-frequency Re-establishment”and the like, the mobile station UE applies the “MeasConfig” afterperforming the procedure described above in detail.

Mobile Communication System According to Third Embodiment of the PresentInvention

Hereinafter, the mobile communication system according to a thirdembodiment of the present invention will be described while focusing onthe difference from the mobile communication system according to theabove-mentioned first embodiment.

In the mobile communication system according to the present embodiment,when a change has occurred in the combinations of the PCC and the SCCsby “Inter-frequency Handover”, “Inter-frequency Re-establishment” andthe like, the mobile station UE is configured to release other types ofconfiguration information related to the SCCs.

That is, the mobile station UE releases configuration informationrelated to the changed SCCs, such as configuration information“RadioResourceConfigDedicated” or “RadioResourceConfigCommon” of L1/L2related to the SCCs, or broadcast information “SystemInformation”related to the SCCs.

Alternatively, the mobile station UE may be configured to release alltypes of configuration information related to the SCCs.

The aspects of the present embodiment as described above may beexpressed as follows.

The first aspect of the present embodiment is summarized as a mobilecommunication method, in which a mobile station UE performs CAcommunication with a radio base station eNB by using PCC (a primarycarrier) and one or a plurality of SCCs (secondary carriers) havingdifferent carrier frequencies, including the steps of: (A) transmitting,from the mobile station UE to the radio base station eNB, “MeasurementReport” including a measurement result of “MeasObject (a measurementobject carrier)”, when “MeasId (a measurement ID)”, the “MeasObject”,and “ReportConfig (a report condition)” are linked and managed, and whenit is determined that the “ReportConfig” is satisfied; and (B)determining, at the mobile station UE, whether or not to release the“MeasId” according to the type of CC designated by the “MeasObject”,when a change has occurred in the combinations of the PCC and the SCCs.

In the first aspect of the present embodiment, in the step (B), when themobile station UE links and manages “MeasId#1 (a first measurement ID)”,“MeasObject#1 (a first measurement object carrier)” for designating “F1(a first carrier)”, and “ReportConfig#1 (a first report condition)”,when the PCC is changed from the “F1” to “F3 (a second carrier)”, andwhen the mobile station UE manages “MeasObject#3 (a second measurementobject carrier)” for designating the “F3”, the mobile station UE maychange the link destination of the “MeasId#1” from the “MeasObject#1” to“MeasObject#3”.

In the first aspect of the present embodiment, in the step (B), when themobile station UE links and manages the “MeasId#1”, the “MeasObject#1”for designating the “F1”, and the “ReportConfig#1”, when the PCC ischanged from the “F1” to the “F3”, and when the mobile station UE doesnot manage the “MeasObject#3” for designating the “F3”, the mobilestation UE may release the “MeasId#1”.

In the first aspect of the present embodiment, in the step B, when the“MeasObject#3”, to which “MeasId#5/#6” has been linked, designates the“SCC”, the mobile station UE may release the “MeasId#5/#6”.

In the first aspect of the present embodiment, in the step (B), when SCCdesignated by the “MeasObject” is continued as SCC even after a changein the combinations of the PCC and the SCCs, the mobile station UE maymaintain the link destination of the “MeasId” linked to the “MeasObject”without a change.

In the first characteristic of the present embodiment, in the step B,when “MeasObject#4”, to which “MeasId#7” has been linked, designates acarrier (Nonconfigured CC) other than the PCC and the SCCs, the mobilestation UE may maintain the link destination of the “MeasId#7” without achange.

In the first aspect of the present embodiment, in the step (B), when thecarrier (Non-configured CC), other than the PCC and the SCCs designatedby the “MeasObject”, is SCC after a change in the combinations of thePCC and the SCCs, the mobile station UE may release the “MeasId” linkedto the “MeasObject”.

The second aspect of the present embodiment is summarized as a mobilestation UE, which is configured to be able to perform CA communicationwith a radio base station eNB by using PCC and one or a plurality ofSCCs having different carrier frequencies, including: a transmissionunit 14 configured to transmit “Measurement Report” including ameasurement result of “MeasObject” to the radio base station eNB, when“MeasId”, the “MeasObject”, and “ReportConfig” are linked and managed,and when it is determined that the “ReportConfig” is satisfied; and ameasurement processing unit 13 configured to determine whether or not torelease the “MeasId” according to the type of CC designated by the“MeasObject”, when a change has occurred in the combinations of the PCCand the SCCs.

In the second aspect of the present embodiment, when “MeasId#1”,“MeasObject#1” for designating “F1”, and “ReportConfig#1” are linked andmanaged by the mobile station UE, when the PCC is changed from the “F1”to “F3”, and when “MeasObject#3” for designating the “F3” is managed bythe mobile station UE, the measurement process unit 13 may be configuredto change the link destination of the “MeasId#1” from the “MeasObject#1”to “MeasObject#3”.

In the second aspect of the present embodiment, when the “MeasId#1”, the“MeasObject#1” for designating the “F1”, and the “ReportConfig#1” arelinked and managed by the mobile station UE, when the PCC is changedfrom the “F1” to the “F3”, and when the “MeasObject#3” for designatingthe “F3” is not managed by the mobile station UE, the measurementprocessing unit 13 may be configured to release the “MeasId#1”.

In the second aspect of the present embodiment, when the “MeasObject#3”,to which “MeasId#5/#6” has been linked, designates the “SCC”, themeasurement processing unit 13 may be configured to release the“MeasId#5/#6”.

In the second aspect of the present embodiment, when SCC designated bythe “MeasObject” is continued as SCC even after a change in thecombinations of the PCC and the SCCs, the measurement processing unit 13may be configured to maintain the link destination of the “MeasId”linked to the “MeasObject” without a change.

In the second aspect of the present embodiment, when “MeasObject#4”, towhich “MeasId#7” has been linked, designates a carrier (Non-configuredCC) other than the PCC and the SCCs, the measurement processing unit 13may be configured to maintain the link destination of the “MeasId#7”without a change.

In the second aspect of the present embodiment, when the carrier(Non-configured CC), other than the PCC and the SCCs designated by the“MeasObject”, is SCC after a change in the combinations of the PCC andthe SCCs, the measurement processing unit 13 may be configured torelease the “MeasId” linked to the “MeasObject”.

The third aspect of the present embodiment is summarized as a mobilecommunication method, in which a mobile station UE performs CAcommunication with a radio base station eNB by using PCC and one or aplurality of SCCs having different carrier frequencies, including: astep of releasing, at the mobile station UE, configuration informationrelated to the SCCs, when a change has occurred in the combinations ofthe PCC and the SCCs.

The fourth aspect of the present embodiment is summarized as a mobilestation UE, which is configured to be able to perform CA communicationwith a radio base station eNB by using PCC and one or a plurality ofSCCs having different carrier frequencies, configured to releaseconfiguration information related to the SCCs, when a change hasoccurred in the combinations of the PCC and the SCCs.

Note that the operation of the mobile station UE or the radio basestation eNB may be performed by hardware, a software module performed bya processor, or a combination thereof.

The software module may be arranged in a storage medium of an arbitraryformat such as a RAM (Random Access Memory), a flash memory, a ROM (ReadOnly Memory), an EPROM (Erasable Programmable ROM), an EEPROM(Electronically Erasable and Programmable ROM), a register, a hard disk,a removable disk, or a CD-ROM.

The storage medium is connected to the processor so that the processorcan write and read information into and from the storage medium. Such astorage medium may also be accumulated in the processor. Such storagemedium and processor may be arranged in an ASIC. The ASIC may bearranged in the mobile station UE or the radio base station eNB.Furthermore, such storage medium and processor may be arranged in themobile station UE or the radio base station eNB as discrete components.

Thus, the present invention has been explained in detail by using theabove-described embodiments; however, it is obvious that for personsskilled in the art, the present invention is not limited to theembodiments explained herein. The present invention can be implementedas a corrected and modified mode without departing the gist and thescope of the present invention defined by the claims. Therefore, thedescription of the specification is intended for explaining the exampleonly and does not impose any limited meaning to the present invention.

INDUSTRIAL APPLICABILITY

As described above, according to the present invention, it is possibleto provide a mobile communication method and a mobile station, withwhich it is possible to appropriately switch and release “MeasId” in CAcommunication.

Reference Signs List

eNB . . . Radio base station

UE . . . Mobile station

11 . . . Re-establishment processing unit

12 . . . Handover processing unit

13 . . . Measurement processing unit

14 . . . Transmission unit

1. A mobile communication method by which a mobile station communicateswith a radio base station by using a primary carrier and one or aplurality of secondary carriers having different carrier frequencies,the method comprising: a step of releasing, at the mobile station, allof configuration information related to the secondary carriers, when achange has occurred in a combination of the primary carrier and thesecondary carriers.
 2. A mobile station configured to be able tocommunicate with a radio base station by using a primary carrier and oneor a plurality of secondary carriers having different carrierfrequencies, wherein when a change has occurred in a combination of theprimary carrier and the secondary carriers, the mobile station isconfigured to release all of configuration information related to thesecondary carriers.